U.S. patent number 4,403,007 [Application Number 06/273,419] was granted by the patent office on 1983-09-06 for filled thermoplastic compositions based on ethylene interpolymers and polyester, polyether and polyether ester plasticizers.
This patent grant is currently assigned to E. I. Du Pont de Nemours & Co.. Invention is credited to Michael C. Coughlin.
United States Patent |
4,403,007 |
Coughlin |
September 6, 1983 |
Filled thermoplastic compositions based on ethylene interpolymers
and polyester, polyether and polyether ester plasticizers
Abstract
Filled thermoplastic compositions useful, e.g., as
sound-deadening sheeting for automotive carpet are obtained by
blending about 5-55% by weight of an ethylene interpolymer, such as
ethylene/vinyl ester, ethylene/unsaturated mono- or dicarboxylic
acids or esters of said unsaturated acids, etc.; about 1-15% by
weight of a plasticizer selected from the group consisting of
polyesters, polyethers, polyether esters and combinations thereof
with processing oil; about 40-90% by weight of filler; and
optionally modifying resins, such as unvulcanized elastomeric
polymers and certain other ethylene and propylene homo- and
copolymers.
Inventors: |
Coughlin; Michael C.
(Wilmington, DE) |
Assignee: |
E. I. Du Pont de Nemours &
Co. (Wilmington, DE)
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Family
ID: |
26872584 |
Appl.
No.: |
06/273,419 |
Filed: |
June 15, 1981 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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176781 |
Aug 11, 1980 |
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Current U.S.
Class: |
428/95; 428/96;
428/97; 524/13; 524/14; 524/15; 524/296; 524/321; 524/377 |
Current CPC
Class: |
D06N
7/0076 (20130101); D06N 2211/263 (20130101); D06N
2203/042 (20130101); D06N 2203/061 (20130101); D06N
2203/06 (20130101); Y10T 428/23993 (20150401); D06N
2209/025 (20130101); D06N 2203/02 (20130101); Y10T
428/23986 (20150401); Y10T 428/23979 (20150401) |
Current International
Class: |
D06N
7/00 (20060101); C08K 005/06 (); C08K 005/10 ();
B32B 027/36 (); B32B 027/32 () |
Field of
Search: |
;524/563,321,559,377,612,296,425,474,427,13,14,15,442,445,437,423,609
;428/95,96,97 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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50-99730 |
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Aug 1975 |
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JP |
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50-151243 |
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Dec 1975 |
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JP |
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940713 |
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Oct 1963 |
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GB |
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Other References
Nakamura et al., Japan Kokai 77,238. .
Nuova Chim., 1972, 48, (12,29-32), Larsen. .
Handbook of Adhesives, (Skeist), 1977, Chapter 30..
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Primary Examiner: Marquis; Melvyn I.
Assistant Examiner: Lilling; Herbert J.
Parent Case Text
This application is a continuation-in-part of my copending
application Ser. No. 176,781 filed Aug. 11, 1980.
Claims
I claim:
1. A composition consisting essentially of (a) from about 5 to
about 55% by weight of at least one copolymer of ethylene with at
least one comonomer selected from the group consisting of vinyl
esters of saturated carboxylic acids wherein the acid moiety has up
to 4 carbon atoms, unsaturated mono- or dicarboxylic acids of 3 to
5 carbon atoms, salts of said unsaturated acids, and esters of said
unsaturated acids wherein the alcohol moiety has 1 to 8 carbon
atoms, the ethylene content of said copolymer being from about 40
to about 95% by weight, the comonomer content of said copolymer
being from about 5 to about 60% by weight, and the melt index of
said copolymer being from about 0.1 to about 150, provided that
when said copolymer of ethylene is an ethylene/vinyl ester or
ethylene/unsaturated mono- or dicarboxylic acid ester copolymer
said copolymer can contain up to about 15 percent by weight of
carbon monoxide or sulfur dioxide; (b) from about 1 to about 15
percent by weight of at least one plasticizer selected from the
group consisting of polyesters, polyethers, polyether esters, and
combinations thereof with processing oil, wherein said polyester is
a liquid condensation product of (.alpha.) dibasic acid selected
from the group consisting of saturated aliphatic dibasic acids and
aromatic dibasic acids and (.beta.) polyol selected from the group
consisting of aliphatic polyols and polyoxyalkylene polyols; (c)
from about 40 to about 90% by weight of filler; (d) from 0 to about
27.5% by weight of unvulcanized elastomeric polymer; and (e) from 0
to about 44% by weight of olefin polymer selected from the group
consisting of low density branched polyethylene, high density
linear polyethylene, linear copolymers of ethylene and another
olefin comonomer, polypropylene and copolymers of propylene and
ethylene where the ethylene content is up to 20% by weight.
2. The composition of claim 1 wherein said elastomeric polymer and
said olefin polymer are present in an amount of 0% by weight.
3. The composition of claim 2 wherein (a) said copolymer of
ethylene is present in an amount of from about 10 to about 50
percent by weight, the ethylene content of said copolymer being
from about 45 to about 90% by weight, the comonomer content of said
copolymer being from about 10 to about 55 percent by weight and the
melt index of said copolymer being from about 0.3 to about 50; (b)
said plasticizer is present in an amount of from about 2 to about
12 percent by weight; and (c) said filler is present in an amount
of from about 50 to about 85 percent by weight.
4. The composition of claim 3 wherein said filler is selected from
the group consisting of calcium carbonate, barium sulfate, hydrated
alumina, clay, magnesium carbonate, calcium sulfate, silica,
flyash, cement dust, wood flour, ground rice hulls and mixtures
thereof.
5. The composition of claim 4 wherein said filler is selected from
the group consisting of calcium carbonate, barium sulfate, hydrated
alumina, and mixtures thereof.
6. The composition of claim 5 wherein said plasticizer is a
polyester that is a liquid condensation product of (a) dibasic acid
selected from the group consisting of saturated aliphatic dibasic
acids and aromatic dibasic acids and (b) polyol selected from the
group consisting of aliphatic polyols and
polyoxyalkylenepolyols.
7. The composition of claim 6 wherein said dibasic acid is selected
from the group consisting of adipic acid, azelaic acid, phthalic
acid, sebacic acid, glutaric acid and mixtures thereof.
8. The composition of claim 7 wherein said polyol is selected from
the group consisting of ethylene glycol, propylene glycol,
1,3-butane glycol, 1,4-butane glycol, diethylene glycol and
polyethylene glycol.
9. The composition of claim 8 wherein more than 50 percent by
weight of the dibasic acids employed are aliphatic dibasic acids
and wherein the polyol is selected from the group consisting of
aliphatic polyols.
10. The composition of claim 9 wherein said dibasic acid is
selected from the group consisting of adipic acid and azelaic acid
and wherein said polyol is selected from the group consisting of
propylene glycol, 1,3-butane glycol and 1,4-butane glycol.
11. The composition of claim 5 wherein said plasticizer is a
polyether selected from polyols based on random or block copolymers
of ethylene oxides or propylene oxides.
12. The composition of claim 5 wherein said plasticizer is a
polyether ester selected from esters of polyols based on polymers
or copolymers of ethylene oxides or propylene oxides.
13. The composition of claim 5 wherein said plasticizer consists
essentially of from about 50 to about 95 percent by weight of
processing oil and from about 5 to about 50 percent by weight of at
least one additional plasticizer selected from the group consisting
of polyesters, polyethers and polyether esters.
14. The composition of claim 13 wherein said plasticizer consists
essentially of from about 50 to about 80 percent by weight
processing oil and from about 20 to about 50 percent by weight of
at least one additional plasticizer selected from the group
consisting of polyesters, polyethers and polyether esters.
15. The composition of claim 5 wherein said copolymer of ethylene
is selected from the group consisting of ethylene/vinyl acetate,
ethylene/acrylic acid and its ionomers, ethylene/methacrylic acid
and its ionomers, ethylene/methyl acrylate, ethylene/ethyl
acrylate, ethylene/isobutyl acrylate, ethylene/normal butyl
acrylate, ethylene/isobutyl acrylate/methacrylic acid and its
ionomers, ethylene/normal butyl acrylate/methacrylic acid and its
ionomers, ethylene/isobutyl acrylate/acrylic acid and its ionomers,
ethylene/normal butyl acrylate/acrylic acid and its ionomers,
ethylene/methyl methacrylate, ethylene/vinyl acetate/methacrylic
acid and its ionomers, ethylene/vinyl acetate/acrylic acid and its
ionomers, ethylene/vinyl acetate/carbon monoxide, ethylene/methyl
acrylate/carbon monoxide, ethylene/normal butyl acrylate/carbon
monoxide, ethylene/isobutyl acrylate/carbon monoxide,
ethylene/vinyl acetate/monoethyl maleate and ethylene/methyl
acrylate/monoethyl maleate.
16. The composition of claim 15 wherein said copolymer of ethylene
is selected from the group consisting of ethylene/vinyl acetate,
ethylene/ethyl acrylate, ethylene/methyl acrylate,
ethylene/isobutylacrylate and ethylene/methyl methacrylate.
17. The composition of claims 5, 8, 11, 12, 14 or 16 wherein (a)
said copolymer of ethylene is present in an amount of from about 15
to about 30 percent by weight; the ethylene content of said
copolymer being from about 60 to about 85 percent by weight, the
comonomer content of said copolymer being from about 15 to about 40
percent by weight, and the melt index of said copolymer being from
about 0.1 to about 10; (b) said plasticizer is present in an amount
of from about 3 to about 8 percent by weight when the filler is
selected from the group consisting of calcium carbonate and
hydrated alumina and from about 4 to about 8 percent by weight when
the filler is barium sulfate; and (c) said filler is present in an
amount of from about 65 to about 80 percent by weight when the
filler is selected from the group consisting of calcium carbonate
and hydrated alumina and from about 70 to about 85 percent by
weight when the filler is barium sulfate.
18. The composition of claims 1, 5, 8, 11, 12, 14 or 16 in the form
of a sound-deadening sheet.
19. A carpet having a backside coating consisting essentially of
the composition of claims 1, 5, 8, 11, 12, 14 or 16.
20. An automotive carpet having a backside coating consisting
essentially of the composition of claims 1, 5, 8, 11, 12, 14 or
16.
21. The composition of claims 6, 11, 12, 14 or 16 containing at
least one modifier selected from the following groups
(d) from 0 to about 27.5% by weight of unvulcanized elastomeric
polymer; and
(e) from 0 to about 44% by weight of olefin polymer selected from
the group consisting of low density branched polyethylene, high
density linear polyethylene, linear copolymers of ethylene and
another olefin comonomer, polypropylene and copolymers of propylene
and ethylene where the ethylene content is up to 20% by weight.
22. The composition of claims 6, 11, 12, 14 or 16 containing at
least one modifier selected from the following groups
(d) unvulcanized elastomeric polymer selected from the group
consisting of styrene-butadiene rubber, polyisobutylene,
ethylene/propylene rubber, and terpolymers of ethylene, propylene
and a diene monomer; and
(e) olefin polymer selected from the group consisting of high
density linear polyethylene, linear copolymers of ethylene and
another olefin comonomer, and copolymers of propylene and ethylene
where the ethylene is up to 20% by weight,
provided that when present at all component (d) is present in an
amount of from about 1 to about 22.5% by weight and component (e)
is present in an amount of from about 1 to about 37.5% by
weight.
23. The composition of claims 6, 11, 12, 14 or 16 containing at
least one modifier selected from the following groups
(d) unvulcanized elastomeric polymer selected from the group
consisting of ethylene/propylene rubber and terpolymers of
ethylene, propylene and a diene monomer, wherein the ethylene
content is from above 20 to about 80% by weight and the diene
content is from 0 to about 5% by weight, said dienes being selected
from the group consisting of methylene norbornene, ethylidene
norbornene, dicyclopentadiene and 1,4-hexadiene; and
(e) olefin polymer selected from the group consisting of high
density linear polyethylene, linear copolymers of ethylene and
another olefin comonomer, and copolymers of propylene and ethylene
where the ethylene content is up to 20% by weight,
provided that when present at all component (d) is present in an
amount of from about 2 to about 12% by weight and component (e) is
present in an amount of from about 3 to about 18% by weight.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to filled blends of ethylene interpolymers
and more specifically it relates to filled blends of ethylene
polymers plasticized with polyester, polyether and polyether ester
plasticizers.
2. Description of the Prior Art
The use of plasticizers with ethylene copolymers generally is not
common. Most ethylene copolymers, of which ethylene/vinyl acetate
copolymers are the most widely used, are used principally to form
films for packaging applications, molded parts, such as shoe soles,
and extruded shapes, such as tubing. Where the benefits of
plasticization such as greater flexibility, are required, the
concentration of comonomer, which acts as an internal plasticizer,
can be adjusted to an appropriate level. In binary blends
containing fillers, physical properties typically suffer with
increasing filler content: melt index decreases, resulting in
higher power requirements for processing; elongation and
flexibility decline, that is, the blends become more brittle; and
modulus increases. These effects can be offset to some degree by
changes in copolymer composition, particularly at low filler
levels. However, the practical limit for addition of medium density
fillers such as calcium carbonate, bauxite, gypsum, etc. is about
60% by weight. As this level is approached physical properties
deteriorate to the point where the mixture is of little practical
use, and it becomes difficult or impossible to prepare homogeneous
blends using standard commercial methods.
Boyer U.S. Pat. No. 3,010,899 discloses blends of ethylene/vinyl
acetate resin and mineral oil which are either rubbery or grease
like depeneding upon the proportion of oil to resin and can be used
as a substitute for crepe rubber or as a grease. It is further
disclosed that fillers such as carbon black or finely divided clays
can be added to the rubbery products to increase hardness and
produce materials suitable as floor tile. As indicated for example
in Claim 11, the filler, carbon black, is present in a
"minor-amount" while the oilethylene/vinyl acetate copolymer
mixture is present in a "major amount".
Nakamura et al. Japan Kokai No. 78 77, 238 discloses the use of a
polyester plasticizer in filled polypropylene with other additives
to improve heat resistance. In a specific example a blend
consisting of 35 parts of polypropylene, 65 parts of calcium
carbonate, 1.3 parts of polyester plasticizer, 0.2 parts of
dimyristyl thiodipropionate, 0.1 parts of calcium stearate, and
0.05 parts of antioxidant gave heat resistance of 520 hr in a
145.degree. C. air oven compared to 230 hr for a control containing
dioctyl phthalate instead of the polyester.
Taira, et al., Japanese Pat. No. 5 0151-243 discloses the use of
magnesium and aluminum silicates in high density polyethylene
plasticized with a polyester plasticizer to improve antistatic
properties. These compositions are disclosed to contain up to 150
parts of filler and 40 parts of polyester plasticizer per 100 parts
of resin.
Lamb et al., U.S. Pat. Nos. 4,085,082, 4,085,083, and 4,111,888,
disclose the use of polyesters prepared from a dibasic acid,
ethylene glycol, and an aliphatic alcohol, from a dibasic acid, a
polyethylene glycol and an aliphatic alcohol, and from a phthalic
acid, ethylene glycol, diethylene glycol or polyethylene glycol and
an aliphatic alcohol, respectively, in unfilled
ethylene/vinyl.sup.3 acetate copolymers containing at least 55%
vinyl acetate. The plasticized compositions provided improved film
clarity and improved extractability.
Larsen in "Action of Additives on High Molecular Weight
Polyethylene" (Nuova Chim. 1972, 48(12), 29-32) describes the use
of plasticizers in blends containing high molecular weight
polyethylene and inert clay fillers to modify processing
characteristics without significantly affecting physical
properties. Polyester plasticizers were one of the types of
plasticizers mentioned.
Schumacher and Yllo U.S. Pat. No. 4,191,798 discloses the use of
processing oils, particularly naphthenic and aromatic oils, in
blends of ethylene interpolymers and fillers. Specifically, the
inclusion of a processing oil in blends of ethylene copolymers and
fillers allows the preparation of higher filler level containing
blends that can be attained in corresponding binary polymer/filler
blends.
In the "Handbook of Adhesives" second edition, edited by Irving
Skeist, published by the Van Nostrand, Reinhold Company in 1977,
Chapter 30 written by J. T. Domine and R. H. Schaufelderg in a
review of hot melt compositions it is disclosed that plasticizers
or liquid modifiers are used to a limited extent in order to impart
properties such as flexibility, specific wetting and viscosity
characteristics to ethylene copolymer based hot melt compositions.
The liquid plasticizers proposed for such use generally speaking
belong to the class of organic esters, however, other liquid
substances, for example, chlorinated polynuclear aromatic compounds
have also been suggested. The particular plasticizer and the
proportion thereof employed in a given composition depends upon
several factors. Important considerations are the cost and
compatibility of the plasticizer with the other ingredients of the
composition, particularly with the ethylene copolymer.
Polyethers and polyether esters are commonly used as surface active
agents in combination with ethylene copolymers. For example,
Japanese Patent Publication No. 099-730/74, (Japanese Patent Appln.
No. 012058/73) discloses the use of up to 15% of polyethylene
glycol sorbitol ester or ether ester surfactant added to unfilled
ethylene/vinyl acetate based hot melt adhesive formulations making
such formulations water soluble.
U.S. Pat. No. 3,492,258, discloses the use of poly(oxyalkylene)
glycol mono-fatty acid esters as release agents in wax coatings
containing ethylene/vinyl acetate copolymers. These release agents
migrate to the surface of the coating and thus impart strippability
to the wax coatings. There is no filler used in these
compositions.
U.S. Pat. No. 3,927,244 discloses a blend of a polyglycol
terephthalate and an ethylene/vinyl acetate copolymer as a
heat-bondable coating on a polyester film. The polyglycol
terephthalate, which is present at a level ranging from 60 to 99.9
wt. % in this blend, is a condensation product of a polyglycol,
such as polyethylene glycol, with a degree of polymerization
ranging from 10 to 100, and terephthalic acid; the degree of
polymerization of the copolymer of the polyglycol and terephthalic
acid ranges from 10 to 500. The function of the polyglycol
terephthalate in this blend is to provide adhesion to the polyester
film substrate; the ethylene/vinyl acetate acts as a toughening
agent where such coatings must survive impact or other abuse. The
addition of fillers such as dyes, organic or inorganic pigments,
and metal powders, at levels ranging up to 200 parts per hundred
based on the polymer blend, is also claimed.
U.S. Pat. No. 3,361,702, discloses polyethylene glycol,
polypropylene glycol, and adducts of propylene oxide with glycerol
and sorbitol, for example, as plasticizers in unfilled compositions
of ethylene/acrylic acid and ethylene/methacrylic acid copolymers,
containing less than 25% by weight of the acid or monomer, and
their sodium salts.
British Pat. No. 940,713 discloses the use of polyethers and
polyether esters with ethylene/vinyl acetate copolymers primarily
for but not limited to, vulcanized compounds. The polyethers
described are homopolymers of ethylene oxide, propylene oxide, or
butylene oxide. The use of fillers is disclosed, silicic acid and
carbon black being mentioned in particular. Although specific
concentrations are not discussed, it is stated that fillers can be
used in very large amounts. The highest filler concentration
disclosed in the examples of this patent was 30 parts filler per
100 parts of ethylene copolymer in a crosslinked composition,
containing other ingredients as well (i.e., about 22-23% filler
based upon the weight of the filled composition).
U.S. Pat. No. 4,242,395 discloses thermoplastic compositions which
are useful as backings for automotive carpets. These compositions
comprise at least 60 percent by weight of inert mineral filler, 5
to 25 percent by weight of an ethylene homopolymer or copolymer
(e.g. ethylene/vinyl acetate, ethylene/ethyl acrylate), 1 to 10
percent by weight of a nonvulcanized elastomeric resin, and 1 to 15
percent by weight of a plasticizer. The plasticizers disclosed
include oils employed in rubber compounds and plasticizers commonly
used with polyvinyl chloride. Of the latter type phthalates,
terephthalates and epoxidized oils were mentioned specifically. The
relatively low molecular weight, liquid plasticizers were indicated
to be preferred. Apparently the preferred hydrocarbon oils and
polyvinyl chloride plasticizers give equivalent property
performance. No specific mention is made of polyesters, or of
polyethers, or their mixtures with hydrocarbon oils, as
plasticizers. It is disclosed that part or all of the ethylene
copolymer can be replaced with polyethylene.
SUMMARY OF THE INVENTION
According to the present invention there is provided a composition
consisting essentially of (a) from about 5 to about 55% by weight
of at least one copolymer of ethylene with at least one comonomer
selected from the group consisting of vinyl esters of saturated
carboxylic acids wherein the acid moiety has up to 4 carbon atoms,
unsaturated mono- or dicarboxylic acids of 3 to 5 carbon atoms, the
salts of said unsaturated acids, and esters of said unsaturated
acids wherein the alcohol moiety has 1 to 8 carbon atoms, the
ethylene content of said copolymer being from about 40 to about 95%
by weight, the comonomer content of said copolymer being from about
5 to about 60% by weight, and the melt index of said copolymer
being from about 0.1 to about 150, provided that when said
copolymer of ethylene is an ethylene/vinyl ester or
ethylene/unsaturated mono- or dicarboxylic acid ester said
copolymer can contain up to about 15% by weight of carbon monoxide
or sulfur dioxide; (b) from about 1 to about 15% by weight of at
least one plasticizer selected from the group consisting of
polyesters, polyethers, polyether esters, and combinations thereof
with processing oil; (c) from about 40 to about 90% by weight of
filler; (d) from 0 to about 27.5% by weight of unvulcanized
elastomeric polymer; and (e) from 0 to about 44% by weight of
olefin polymer selected from the group consisting of low density
branched polyethylene, high density linear polyethylene, linear
copolymers of ethylene and another olefin comonomer, polypropylene
and copolymers of propylene and ethylene where the ethylene content
is up to 20% by weight.
Further provided according to the present invention are the above
compositions in the form of a sound deadening sheet.
Still further provided according to the present invention are
carpets and especially automotive carpets having a backside coating
consisting essentially of the above compositions.
As used herein the term "consisting essentially of" means that the
named ingredients are essential, however, other ingredients which
do not prevent the advantages of the present invention from being
realized can also be included.
DETAILED DESCRIPTION OF THE INVENTION
It has been found that the use of a polyester, polyether or
polyether ester plasticizer in blends of ethylene copolymers and
fillers imparts a balance of properties not found in similar
compositions of this type where other types of plasticizers are
used. In particular, an unusual degree of flexibility and toughness
is obtained which is not normally achieved, especially at high
filler concentrations.
The ethylene copolymers suitable for the composition of the present
invention are copolymers with at least one comonomer selected from
the group consisting of vinyl esters of saturated carboxylic acids
wherein the acid moiety has up to 4 carbon atoms, unsaturated mono-
or dicarboxylic acids of 3 to 5 carbon atoms, the salts of said
unsaturated acids, and esters of said unsaturated acids wherein the
alcohol moiety has 1 to 8 carbon atoms. Terpolymers of ethylene and
the above comonomers are also suitable. Ionomers, which are the
completely or partially neutralized copolymers of ethylene and the
acids described above, are discussed in more detail in U.S. Pat.
No. 3,264,272. In addition, terpolymers of ethylene/vinyl
acetate/carbon monoxide or ethylene/methyl acrylate/carbon monoxide
containing up to about 15% by weight of carbon monoxide can also be
employed.
The ethylene content of the copolymer is from about 40 to about 95%
by weight and the comonomer content is from about 5 to about 60% by
weight. The preferred ethylene and comonomer level is from about 45
to about 90% and from about 10 to about 55% by weight,
respectively. Most preferably the ethylene and comonomer level is
from about 60% to about 85% and from about 15 to about 40% by
weight, respectively. A mixture of two or more ethylene copolymers
can be used in the blends of the present invention in place of a
single copolymer as long as the average values for the comonomer
content will be within the above indicated range. Significant,
unexpected improvements, especially in tensile elongation, obtained
by the use of certain combinations of at least two ethylene
copolymers in place of a single ethylene copolymer are the subject
matter of applications Ser. No. 176,782 filed Aug. 11, 1980, Ser.
No. 251,989, filed Apr. 6, 1981, and simultaneously being filed
application Ser. No. 273,420, filed June 15, 1981 now U.S. Pat. No.
4,379,190 the disclosure of applications are hereby incorporated by
reference.
Melt index of the copolymer can range from about 0.1 to about 150,
preferably from about 0.3 to about 50, and most preferably from
about 0.7 to about 10.
Physical properties, principally elongation, decline to lower
levels when the ethylene copolymer melt index is above about 30. A
lower melt index range, about 0.7 to 10, is most preferred to
maintain strength.
Generally from about 5 to about 55% by weight of ethylene copolymer
is employed in the composition of the present invention, preferably
from about 10 to about 50% by weight, and most preferably, from
about 15 to 30% by weight.
In accordance with the above, suitable ethylene copolymers include
ethylene/vinyl acetate, ethylene/acrylic acid and its ionomers,
ethylene/methacrylic acid and its ionomers, ethylene/methyl
acrylate, ethylene/ethyl acrylate, ethylene/isobutyl acrylate,
ethylene/normal butyl acrylate, ethylene/isobutyl
acrylate/methacrylic acid and its ionomers, ethylene/normal butyl
acrylate/methacrylic acid and its ionomers, ethylene/isobutyl
acrylate/acrylic acid and its ionomers, ethylene/normal butyl
acrylate/acrylic acid and its ionomers, ethylene/methyl
methacrylate, ethylene/vinyl acetate/methacrylic acid and its
ionomers ethylene/vinyl acetate/acrylic acid and its ionomers,
ethylene/vinyl acetate/carbon monoxide, ethylene/methyl
acrylate/carbon monoxide, ethylene/normal butyl acrylate/carbon
monoxide, ethylene/isobutyl acrylate/carbon monoxide,
ethylene/vinyl acetate/monoethyl maleate and ethylene/methyl
acrylate/monoethyl maleate. Particularly suitable copolymers are
ethylene/vinyl acetate, ethylene/ethyl acrylate, ethylene/methyl
acrylate, ethylene/isobutyl acrylate, and ethylene/methyl
methacrylate copolymers.
Unvulcanized elastomeric polymers are of interest as modifying
resins for the blends of the present invention. They exhibit good
compatibility in the blends and can be useful for obtaining
increased flexibility and/or melt strength. When these polymers are
used in combination with the ethylene copolymers described
previously, they can range in concentration from 0 to about 27.5%
by weight, preferably from about 1 to about 22.5% by weight, and
most preferably from about 2 to about 12% by weight of the
composition of the present invention. A variety of different
rubbers can be used including styrene-butadiene rubber,
polyisobutylene, ethylene/propylene rubbers, and terpolymers of
ethylene, propylene, and a diene monomer (EPDM). Preferred rubbers
are the ethylene/propylene and the EPDM polymers in which the
ethylene content can range from above 20% by weight to about 80% by
weight. The diene comonomer is usually methylene norbornene,
ethylidene norbornene, dicyclopentadiene, or 1,4-hexadiene,
although other dienes may be used, and the concentration of the
diene is usually less than 5% by weight. The Mooney viscosity is
preferably in the range of 20 to 90.
Another class of modifying resins useful in the practice of this
invention are the low density branched homopolymers of ethylene,
the high density linear homopolymers of ethylene, the linear
copolymers of ethylene and another olefin monomer, homopolymers of
propylene, and copolymers of propylene and ethylene where the
ethylene content is up to 20% by weight. For reasons of
compatibility and the balance of properties obtained, the preferred
materials are the high density ethylene homopolymers, the linear
copolymers of ethylene and another olefin, and the copolymers of
propylene and ethylene. The olefin content and the olefins used in
the linear copolymers are described in U.S. Pat. No. 4,076,698. The
propylene/ethylene copolymers may contain up to 20% by weight
ethylene. When used in combination with the ethylene copolymers
described previously in compounds of the present invention,
materials with an unusual range of properties result. These
properties include the high density useful in sound deadening
applications, low cost due to the high filler content, good
toughness due to the presence of the ethylene copolymers and to the
use of the polyester and the polyether plasticizers of this
invention, very high stiffness due to the modifying resins, and
good adhesion due to the presence of the ethylene copolymer(s)
described previously. The members of this class of modifying resins
can be present in an amount of from 0 to about 44% by weight,
preferably from about 1 to about 37.5% by weight, and most
preferably from about 3 to about 18% by weight of the composition
of the present invention.
The polyester plasticizer component of the present invention is, in
general, a liquid, condensation product of a polybasic acid and a
polyol. The term "liquid" in the context of the present invention
is used to mean pourable at room temperature. The acid component is
most often a saturated aliphatic dibasic acid or an aromatic
dibasic acid; adipic acid, azelaic acid, phthalic acid, sebacic
acid, and glutaric acid, or mixtures of these acids are commonly
used. The polyol can be an aliphatic polyol or a poly oxyalkylene
polyol, such as, ethylene glycol, propylene glycol, 1,4- and
1,3-butane glycol, diethylene glycol, and polyethylene glycol.
Preferred polyester compositions would consist of an acid component
of which greater than 50% by weight are aliphatic dibasic acids,
and a polyol component of aliphatic polyol or even more preferably
aliphatic glycol. Most preferred compositions are based on adipic
or azelaic acid, and propylene glycol or the 1,3- or 1,4-butane
glycol. The molecular weight of these plasticizers can vary from a
low of a few hundred up to a high of about 10,000. The molecular
weight of commercial products is seldom specified; however,
typically in the trade, the molecular weight range of the product
is classified as low, medium, or high. The preferred range for
purposes of this invention is that classified as medium.
Mixtures of polyesters with hydrocarbon oils are also effective
plasticizers in the present invention. One objective of using such
a mixture is to couple the high efficiency of the relatively high
cost polyester with the low cost of the hydrocarbon oil. The
cost/performance of a compound plasticized with such a mixture can
be improved significantly for a given application because
properties can be tailored more precisely, or filler levels can be
increased. Actually certain advantages in the performance of the
blends of the present invention are obtained as will be discussed
below, when such a mixture is used as the plasticizer.
The oil ingredient of the composition of the present invention is
known as processing oil. Three types of processing oils are
known--paraffinic, aromatic and naphthenic. None of these are pure,
the grades identify the major oil type present.
Paraffinic oils tend to "bleed" from blends. Bleeding is normally
not desirable, but could be useful in specialty applications, for
example, in concrete forms where mold release characteristics are
valued.
On the other hand, naphthenic and aromatic oils are nonbleeding
when used in proper ratios and are thus preferable.
Processing oils are also subdivided by viscosity range. "Thin" oils
can be as low as 100-500 SUS (Saybolt Universal Seconds) at
100.degree. F. (38.degree. C.). "Heavy" oils can be as high as 6000
SUS at 100.degree. F. (38.degree. C.). Processing oils, especially
naphthenic and aromatic oils with viscosity of from about 1500 to
6000 SUS at 100.degree. F. (38.degree. C.) are preferred.
Considerations in selection of the processing oil relative to
compatibility for purposes of the compositions of the present
invention are as set out in detail in Schumacher and Yllo U.S. Pat.
No. 4,191,798, the disclosure of which is hereby incorporated by
reference.
When used alone, the amount of polyester plasticizer in the
composition of the present invention is from about 1 to about 15%
by weight, preferably from about 2 to about 12% by weight. Most
preferably when using a filler of medium density, such as calcium
carbonate, the amount of plasticizer is from about 3 to about 8% by
weight, and when using a filler of higher density, such as barium
sulfate, the amount of plasticizer is from about 4 to about 8% by
weight.
Where a mixture of the polyester plasticizer and a hydrocarbon oil
is employed, the relative proportions of the two components can be
varied over a wide range depending upon performance objectives.
Mixtures containing 50% or less of the polyester are preferred for
economic reasons, and most preferred are those containing 20% or
less of the polyester.
A separate class of plasticizers, polyethers and polyether esters,
are also effective plasticizers in blends of the ethylene
copolymers and fillers described above. In general, polyethers are
oligomers or polymers of alkylene oxides; polymers of ethylene or
propylene oxide are the most common types available commercially.
Polyethers can be prepared by polymerization of aldehydes using
various types of catalysts, or by acid or base catalyzed
polymerization of an alkylene oxide, for example. Polyethers can be
terminated by hydroxyl groups to form the diol (glycol) or, in the
case of adducts of alkylene oxides with glycerol, for example, the
triol, and so forth. The hydroxyl terminated polyether can also be
reacted with an acid, fatty acids such as lauric and stearic acids
are commonly used, to form the ester; the most common examples of
these compounds are the mono- and diesters of polyethylene or
polypropylene glycol. The molecular weight of polyethers may range
up to those typical of high polymers.
Preferred polyether compositions in the practice of this invention
are those consisting of the polyols based on random and/or block
copolymers of ethylene oxides and propylene oxides. The copolymer
polyols provide better performance in terms of efficiency in
compounds of the present invention containing very high levels of
filler. Examples 25 and 27, in which a triol based on a random
copolymer of ethylene oxide and propylene oxide and a triol based
on propylene oxide only, respectively, are compared in compounds
containing >70% filler, demonstrate this clearly.
The amount of polyether plasticizer in the composition of the
present invention is from about 1 to about 15% by weight,
preferably from about 2 to about 12% by weight. Most preferably,
when using a filler of medium density, such as calcium carbonate,
the amount of plasticizer is from about 3 to 8% by weight, and when
using a filler of higher density, such as barium sulfate, the
amount of plasticizer is from about 4 to about 8% by weight.
Mixtures of the polyether or the polyether ester plasticizers with
either a polyester plasticizer or a hydrocarbon processing oil can
also be used in the practice of this invention. The advantage of
polyether/polyester combination is the lower cost since the
polyethers are cheaper than the polyesters. Combinations of
polyether and processing oil are also cheaper because of the lower
cost of the oil.
The relative proportions of the two components in a
polyether/polyester combination will be adjusted according to the
efficiency of the system based on property requirements and cost.
Those based on polyester primarily will not be as stiff and will be
more expensive, for example, then those based primarily on a
polyether or polyether ester.
Where a mixture of the polyether or polyether ester and a
hydrocarbon oil is employed, the relative proportions used will
again depend upon cost and property requirements. Since the
polyethers are more expensive than the processing oils, mixtures
containing 50% or less of the polyethers are preferred.
As referred to above a mixture of processing oil, on the one hand,
and polyester or polyether or polyether ester, or any combination
thereof, on the other hand, can also be used very effectively as
the plasticizer for the compositions of the present invention. In
fact, such a two- or more component plasticizer system, comprising
from about 50 to about 95 percent by weight of processing oil,
gives higher tensile elongation than can be obtained using either
plasticizer alone at the same level. Maximum elongation is achieved
using a mixture of processing oil and polyester or polyether or
polyether ester or any combination thereof comprising from about 50
to about 80 percent by weight of processing oil.
Where a mixture of plasticizers is used, the amount of plasticizer
may range from about 2 to about 15% by weight, preferably from
about 4 to about 12% by weight. Most preferably when using a filler
of medium density, such as calcium carbonate, the amount of
plasticizer is from about 5 to about 10% by weight, and when using
a filler of higher density, such as barium sulfate, the amount of
plasticizer is from about 4 to about 8% by weight.
The third essential ingredient of the composition of the present
invention is the filler. The percentage of filler that can be
included in the composition of the present invention on a weight
basis is primarily a function of the density of the filler.
Particle size of the filler has some effect. Fine particle size
fillers generally have a tendency to result in higher blend
viscosities, and they are also more expensive. The use of fine
filler, especially at high filler loading, results in a smoother
extrudate surface when molten blend is extruded through a die
orifice. The attendant benefits of using fine particle size filler
in filled polymer blends are described in patent application Ser.
No. 052,927 filed June 27, 1979, issued on Apr. 21, 1981 as U.S.
Pat. No. 4,263,196 the disclosure of which is hereby incorporated
by reference. No. 9 Whiting (calcium carbonate) which has been used
extensively in the present compositions (about 95 percent through
325 mesh) represent a viable midpoint in coarseness, availability,
and cost.
Examples of suitable fillers are calcium carbonate, barium sulfate,
hydrated alumina, clay, magnesium carbonate, calcium sulfate,
silica, flyash, cement dust, wood flour, ground rice hulls and
mixtures thereof.
Most preferred fillers are calcium carbonate, barium sulfate,
hydrated alumina, and mixtures thereof.
The amount of filler used may range from about 40 to about 90
percent by weight. Where higher density compositions are needed,
particularly for sound deadening applications, the preferred filler
concentration will range from about 50 to about 85 percent by
weight. Most preferably, when using a filler of medium density,
such as calcium carbonate, or hydrated alumina the amount of filler
is from about 65 to about 80 percent by weight, and when using a
filler of higher density, such as barium sulfate, the amount of
filler is from about 70 to about 85 percent by weight.
Polymers, both homo- and copolymers, other than the ones referred
to above, can also be used to some extent in combination with the
above specified polymers without significantly interfering with the
advantages obtained by the present invention. Similarly other
ingredients can also be added to the compositions of the present
invention by a compounder in order to obtain some desired effect,
such as reduction of cost, or enhancement of physical property.
Accordingly, extender resins, waxes, foaming agents, crosslinking
agents, antioxidants, flame retardant agents, etc. that are widely
used, can be included in the compositions of the present
invention.
The blends of the present invention are thermoplastic in nature and
therefore can be recycled after processing. The recycled material
may also contain textile fibers, jute, etc. present in the trim
obtained during production of the finished product (e.g.,
back-coated automotive carpet).
A commercially sized batch-type Banbury or equivalent intensive
mixer is entirely suitable for preparing the compositions of the
present invention. A Farrel continuous mixer ("FCM") is also an
excellent mixing device. In either instance, dry ingredients are
charged in routine fashion. It is convenient in most cases to
inject the plasticizer component directly into the mixing chamber
of either unit as per widely used practice with this type of
equipment. When more than one plasticizer is used, and where any
one of the plasticizers is present in a small amount (less than
about 10 weight percent of the total plasticizer mixture), the
plasticizers should be preblended before addition to the other
ingredients of the present invention. This will facilitate uniform
distribution of each plasticizer component in the final composition
and thus ensure that optimum properties are obtained. If desired,
the copolymer and the plasticizer(s) can be precompounded as a
"Masterbatch" in a suitable intensive mixing device (e.g., Banbury
mixer or screw extruder). This "Masterbatch" can then be compounded
with the filler and the other remaining ingredients to produce the
final composition. A mix cycle of about 3 minutes is generally
adequate for the Banbury mixer at an operating temperature usually
between 325.degree. and 375.degree. F. The operating rate for the
FCM unit generally will fall within ranges predicted by literature
prepared by the Farrel Company, Ansonia, Connecticut. Again,
temperatures between 325.degree. and 375.degree. F. are effective.
In both cases, a very low plasticizer level, say about 2-3%, may
require higher temperatures, while plasticizer levels above about
7% may mix well at lower mixer temperatures. While not evaluated,
it is expected that other devices for handling viscous mixes (MI of
0.1 to 20) should be entirely satisfactory--but in any case,
prototype trials in advance are desirable.
Once blends are mixed, routine commercial practices may be used,
such as underwater melt cutting plus drying or use of sheeting plus
chopping methods, to produce a final pelletized product.
Primary use for the compositions of the present invention will
probably be in the sheeting field, particularly for low cost,
dense, sound deadening structures. Outstanding characteristics such
as improved "hand", "drape", reduced stiffness, and reduced
thickness of the extruded sheeting result from the compositions of
the present invention.
Other uses are possible. The principal advantage of this invention
is that certain physical properties, such as flexibility and
toughness, which are typically reduced when fillers are added to
polymers, can be maintained within useful limits over a broad range
of filler concentrations. Thus, this invention could be used in the
manufacture of wire and cable compounds, of various molded parts,
of sealants and caulks, or in other uses where flexibility and
toughness are desired, coupled with the economies normally achieved
by the incorporation of low cost fillers.
The blends of the present invention can readily be extruded onto a
substrate, such as an automotive carpet, or can be extruded or
calendered as unsupported film or sheet. Depending upon the
equipment used, and the compounding techniques employed, it is
possible to extrude wide range of film thickness, from below 20
mils to above 100 mils. This then provides industry with an
opportunity to vary the amount of sound deadening to be attained by
varying film thickness, density of blends, ratio of filler load to
binder, and similar techniques well known in the art.
The sound-deadening sheet produced may be used in various ways:
When applied to automotive carpet, blends described are an
effective and economic means to deaden sound, while also
simultaneously serving as a moldable support for the carpet.
When used in sheet form, the blends can be installed in other areas
of an automobile, truck, bus, etc., such as side panels, door
panels, roofing areas, etc.
In sheet form, blends may be used as drapes or hangings to shield
or to surround a noisy piece of factory equipment such as a loom, a
forging press, etc.
In laminated sheet form, blends, faced with another material, might
be used to achieve both a decorative and a functional use--such as
dividing panels in an open-format office.
The application of the compositions of the present invention in
carpets, and particularly in automotive carpets, is essentially
identical to the methods as already described in U.S. Pat. No.
4,191,798, the disclosure of which is hereby incorporated by
reference.
The following examples are given for the purpose of illustrating
the present invention. All parts and percentages are by weight
unless otherwise specified.
EXAMPLE 1 AND COMPARATIVE EXAMPLES 1 TO 7
These examples compare a compound prepared according to the present
invention (Example 1) to similar compounds containing a variety of
different plasticizers. Included is a useful composition based on
U.S. Pat. No. 4,191,790 (comparative Example 1).
The basic composition used was
16.2% EVA #1 (25% vinyl acetate, 75% ethylene, 2.5 MI)
4.0% EVA #2 (7.5% vinyl acetate, 92.5% ethylene, 1.2 MI)
7.3% Plasticizer
72.5% #9 "Whiting" (calcium carbonate, as commercial ground
limestone; Georgia Marble Co.)
The plasticizers used are indicated in Table I together with the
results of physical property measurements. All of the blends were
mixed on a two roll mill operating at 150.degree.-170.degree. C.
The polymers were first added to the mill; after banding, all of
the plasticizer was added gradually over a period of 1 to 2 min.
The filler was then added gradually over a period of 1 to 2
minutes. All of the ingredients were then milled for an additional
5 minutes.
The compounds of examples C1 to C6 are very similar to one another
in terms of their physical properties: the materials were somewhat
rigid with flexural moduli ranging from about 13 to 18 Kpsi (92 to
126 Mpa), and elongation and tensile impact strength were very low.
All of these samples were fairly brittle in that they could be
broken easily when bent (see crease test results), with the
exception of example C1, which only cracked slightly when folded.
The compound of example C7 was very brittle and would be of little
use commercially. However, the compound of Example 1 containing the
polyester plasticizer was very flexible and showed no tendency to
crack in the crease test; elongation and impact toughness were
excellent considering the filler level of 70+%.
TABLE I ______________________________________ COMPARISON OF
PLASTICIZER TYPES ______________________________________ Circosol
Plasticizer 4240.sup.(1) DOA.sup.(2) DOS.sup.(3) DOZ.sup.(4)
DOP.sup.(5) ______________________________________ Example No. C1
C2 C3 C4 C5 Density, g/cc 1.78 1.79 1.76 1.77 1.81 Flexural
Modulus.sup.(9) MPa 125.5 101.4 92,4 91.7 101.4 kpsi 18.2 14.7 13.4
13.3 14.7 Tensile Strength.sup.(10) MPa 2.8 3.4 2.9 2.4 3.2 kpsi
400 496 424 348 466 Tensile Elonga- tion.sup.(10) % 23 23 23 23 23
Tensile Impact.sup.(11) J/m.sup.2 40,100 30,100 30,400 20,800
31,800 ft-lb/in..sup.(2) 19.1 14.3 14.5 9.9 15.1 Crease
Test.sup.(12) P.sup.- F F F F
______________________________________ Phthalyl Plasticizer
Glycolate.sup.(6) Sulfonamide.sup.(7) Polyester.sup.(8)
______________________________________ Example No. C6 C7 1 Density
1.80 1.91 1.81 Flexural Modulus.sup.(9) MPa 121.4 371 27.6 kpsi
17.6 53.8 4.0 Tensile Strength.sup.(10) MPa 2.4 4.9 1.7 kpsi 350
717 252 Tensile Elongation % 23 23 335 Tensile Impact.sup.(11)
J/m.sup.(2) 4260 50,500 159,200 ft-lb/in..sup.2 2 24.1 75.8 Crease
Test.sup.(12) F F P ______________________________________ .sup.(1)
Naphthenic processing oil, Sun Oil Co.; viscosity 2525 Saybolt
Universal Seconds at 100.degree. F. .sup.(2) Dioctyl adipate
.sup.(3) Dioctyl sebacate .sup.(4) Dioctyl azelate .sup.(5) Dioctyl
phthalate .sup.(6) "Santicizer" 316, Monsanto; butyl phthalyl butyl
glycolate .sup.(7) "Santicizer" 8, Monsanto; N--ethylo- and
ptoluene-sulfonamide .sup.(8) "Admex" 529, Ashland Oil Co., see
Table III for further product information .sup.(9) ASTM D790, 0.2
inches/min; 0.050" (1.27 mm) nominal compression molded plaque
.sup.(10) ASTM D1708, 2 inches/min; 0.050" (1.27 mm) nominal molded
laque .sup.(11) ASTM 1822, type S; 0.50" (1.27 mm) nominal
compression molded plaque .sup.(12) Deadbend crease; sample is
folded sharply back upon itself (deadbend). P = Pass, P.sup.- =
slight cracking at the fold edge, F = sample cracked at the
fold.
EXAMPLES 2 TO 4
The composition of Example 2 was prepared on a two roll mill as
described for Example 1 above. The compositions of Examples 3 and 4
were blended in a Banbury mixer. All of the ingredients were first
charged into the chamber in an amount adequate to fill the entire
chamber. The chamber was then closed using a ram pressure of 25
psi. The ingredients were mixed for 31/2 minutes at a rotor speed
of 280 rpm after the temperature leveled out; the maximum was
350.degree. F. (180.degree. C.).
The basic composition used was
16.2% EVA #1
4.0% EVA #2
7.3% polyester plasticizer
72.5% #9 "Whiting"
The polyester plasticizers used are indicated in Table II with
physical properties of the compounds.
The data show that all of the polyester plasticizers examined in
this comparison yield both similar reductions in flexural modulus
and significantly improved elongation and impact strength. Although
there seem to be some differences in performance among the
polyesters, the differences are fairly small and the selection of
plasticizer would probably be based on cost rather than the
differences observed here.
All of the plasticizers of these Examples consist of condensation
products of aliphatic dibasic acids and glycols. The "Santicizer"
334F, for example, consists of an acid component of adipic acid,
and glycol component of 1,3-butane glycol. "Paraplex" G-25, as
another example, consists of sebacic acid and propylene glycol.
Infrared analysis confirms that the other two plasticizers ("Admex"
529 and "Santicizer" 429) consist of essentially similar
components. Other property data are summarized in Table III. There
appears to be no correlation between the performance of the
polyester plasticizers in the blends and the properties shown in
Table II as well as the other properties of the polyesters, such as
acid number, which varies in these plasticizers by a factor of 4,
and viscosity, which varies by two orders of magnitude.
EXAMPLES 5 TO 9
The compositions of these Examples were prepared in a Banbury mixer
as described for Examples 3 and 4. All of these compounds contained
72.5% #9 "Whiting" nominally. The proportions of the remaining two
components, the polymer and plasticizer, were adjusted relative to
one another. The polymer used was an 18% vinyl acetate, 82%
ethylene copolymer with a 2.5 melt index. The plasticizer was
"Santicizer" 334F. The data are summarized in Table IV.
TABLE II ______________________________________ POLYESTER
PLASTICIZERS "Santici- "Santi- "Paraplex" "Admex" cizer" cizer"
Plasticizer G-25.sup.1 529.sup.1 334F.sup.1 429.sup.1
______________________________________ Example No. 2 1 3 4 Density,
g/cc 1.79 1.81 1.78 1.83 Flexural Modulus MPa 15.8 27.6 18.6 55.8
kpsi 2.3 4.0 2.7 8.1 Tensile Strength MPa 2.2 1.7 1.9 2.0 psi 318
252 280 297 Tensile Elonga- tion % 438 335 365 362 Tensile Impact
J/m.sup.2 165,800 159,200 121,300 134,900 ft-lb/in..sup.2 79 75.8
57.8 64.2 Crease Test P P P P
______________________________________ .sup.(1) The plasticizers
are described in detail in Table III.
TABLE III ______________________________________ POLYESTER
PLASTICIZERS PHYSICAL PROPERTY DATA "Santi- "Santi- cizer" cizer"
"Paraplex" "Admex" 334F 429 G-25 529
______________________________________ Molecular Weight .sup.(1)
.sup.(1) 8000.sup.(2) .sup.(1) Specific Gravity 1.082 1.10 1.06
1.12 Freezing Point, .degree.C. -- <-60 15 -- Acid Number mg
KOH/g 0.7 2.2 1.4 3 Viscosity @ 25.degree. C. 35 55 2200 55
______________________________________ Note: .sup.(1) Described as
medium molecular weight. .sup.(2) Described as high molecular
weight.
TABLE IV ______________________________________ EFFECT OF
PLASTICIZER CONTENT ______________________________________ Polymer
Content Wt. % 20.2 21.8 23.3 25.4 26.9 Plasticizer Content, Wt. %
7.3 5.7 4.2 2.1 1 Example No. 5 6 7 8 9 Density g/cc 1.79 1.79 1.82
1.74 1.77 Flexural Modulus MPa 17.9 40.7 90.3 321 340 kpsi 2.6 2.9
13.1 46.6 49.2 Tensile Strength MPa 1.8 2 2.6 3 5.6 psi 260 290 372
430 813 Tensile Elongation % 274 282 354 68 23 Tensile Impact
J/m.sup.2 129,000 160,000 198,000 (*) 6900 ft-lb/in..sup.2 61 76 89
3.3 Crease Test P P P P P.sup.-
______________________________________ (*) Too brittle to
measure
The data illustrate clearly the attractive balance of properties
achievable at this high filler level by adjusting plasticizer
content. Also, comparison of the properties of Example 7 with those
of Example C1, Table I, again demonstrate the unique behavior of
the polyester plasticizer. That is, at reasonably comparable
modulus and tensile strength, the compound plasticized with the
polyester had markedly better elongation, flexibility (i.e., flex
crack resistance) and tensile impact strength.
EXAMPLE 10
The composition of Example 10 containing 80% by weight filler was
prepared in a Banbury mixer as described in Examples 3 and 4. The
composition and its physical properties are summarized in Table V.
The data show that the polymer and plasticizer content can be
reduced significantly and still one can obtain physical properties
which would probably be adequate as a sound deadening backing for
carpeting.
EXAMPLES 11 TO 16 AND COMPARATIVE EXAMPLE 8
All examples were prepared in a Banbury mixer as described in
Examples 3 and 4. The basic composition of Examples 11 to 16
was
20.2% Polymer
7.3% "Santicizer" 334F
72.5% #9 "Whiting"
The polymers used and the properties of the compositions are listed
in Table VI. The composition of Example C8 was similar to that of
Example 15 with the exception that "Circosol" 4240 was used as a
plasticizer instead of "Santicizer" 334F.
The data show that with increasing vinyl acetate content of the
copolymer component, flexural modulus generally decreases,
elongation and tensile impact strength generally increase. Also,
the properties of Example 11, containing a copolymer with only 7.5%
vinyl acetate, are probably adequate as a sound deadening backing
for carpeting. Finally, a comparison of Example 15 and C8 again
show how flexibility, in terms of flexural modulus and flex crack
resistance, and toughness are improved when the polyester
plasticizer is used.
TABLE V ______________________________________ EFFECT OF FILLER
CONCENTRATION ______________________________________ EVA #1 Wt. %
16.2 11.8 EVA #2 Wt. % 4.0 2.9 "Santicizer" 334F Wt. % 7.3 5.3
Filler Level Wt. % 72.5 80 Example No. 3 10 Density g/cc 1.78 1.99
Flexural Modulus MPa 18.8 90 kpsi 2.7 13 Tensile Strength MPa 2 1.2
psi 280 179 Tensile Elongation % 365 304 Tensile Impact J/m.sup.2
121,300 74,000 ft-lb/in..sup.2 57.8 35 Crease Test P P
______________________________________
TABLE VI
__________________________________________________________________________
COMPARISON OF COPOLYMER VAc CONTENT
__________________________________________________________________________
VAc Content, % 7.5.sup.(1) 9.3.sup.(2) 12.sup.(3) 15.sup.(4)
18.sup.(5) 25.sup.(6) 18.sup.(5) Example # 11 12 13 14 15 16 C8
Density g/cc 1.76 1.79 1.79 1.76 1.78 1.79 1.78 Flexural Modulus
MPa 89.6 44.8 51 30.3 32.4 26.2 179 kpsi 13.0 6.5 7.4 4.4 4.7 3.8
25.9 Tensile Strength MPa 1.9 1.9 1.7 1.8 1.7 2.2 4.4 psi 278 270
244 258 246 313 640 Tensile Elongation % 110 145 148 202 255 438 23
Tensile Impact J/m.sup.2 22,500 32,600 86,200 141,000 131,000
162,000 36,000 ft-lb/in..sup.2 10.7 15.5 41 66.9 62.3 77.2 17.1
Crease Test P.sup.- P P P P P F
__________________________________________________________________________
.sup.(1) EVA #2 .sup.(2) EVA #3: 9.3% vinyl acetate, 90.7%
ethylene; 2.0 MI .sup.(3) EVA #4: 12% vinyl acetate, 88% ethylene;
2.5 MI .sup.(4) EVA #5: 15% vinyl acetate, 85% ethylene; 2.5 MI
.sup.(5) EVA #6: 18% vinyl acetate, 82% ethylene; 2.5 MI .sup.(6)
EVA #1
EXAMPLES 17 TO 19
All of these examples were prepared in a Banbury mixer as described
in Examples 3 and 4. The basic composition used was
20.2% Polymer
7.3% "Santicizer" 334F
72.5% #9 "Whiting"
The polymers used are listed in Table VII together with physical
properties of the blends.
The data suggest that as the melt index of the copolymer component
is reduced, plasticizer efficiency improves somewhat, as indicated
by the reduction in flexural modulus. Tensile strength also
increases slightly; elongation and tensile impact strength increase
significantly. In general, all the properties measured improved.
However, the properties of Example 19 containing the copolymer with
a melt index of 150 have generally declined, but are probably still
acceptable as a sound deadening backing for carpeting.
EXAMPLES 20 AND 21
Examples 20 and 21 were prepared on a two roll mill as described in
Example 1. The composition used was
20.2% Polymer
7.3% "Santicizer" 334F
72.5% "#9 Whiting"
The polymers used are listed in Table VIII together with the
physical properties. The compounds are examples of the most
preferred compositions. The data demonstrate both the range of
properties available in this type of composition and the basic
equivalence of the compound based on the two different types of
copolymers. This basic formulation would be a logical starting
point for a compounder because it offers an excellent balance of
properties.
TABLE VII ______________________________________ EFFECT OF POLYMER
MELT INDEX ______________________________________ VAc Level, %
12.sup.(1) 12.sup.(2) 18.sup.(3) 18.sup.(4) 18.sup.(5) Melt Index
g/10 min 2.5 0.35 2.5 0.7 150 Example No. 13 17 15 18 19 Density
g/cc 1.79 1.76 1.78 1.79 1.81 Flexural Modulus MPa 51 42.7 32.4
23.4 27.6 kpsi 7.4 6.2 4.7 3.4 4 Tensile Strength MPa 1.7 2 1.7 2.4
0.6 psi 244 285 246 344 84 Tensile Elongation % 148 167 255 335 80
Tensile Impact J/m.sup.2 86,200 144,000 131,000 164,000 31,100
ft-lb/in..sup.2 41 68.8 62.3 78.0 14.8 Crease Test P P P P P
______________________________________ .sup.(1) EVA #4 .sup.(2) EVA
#7: 12% vinyl acetate, 88% ethylene; 0.35 MI .sup.(3) EVA #6
.sup.(4) EVA #8: 18% vinyl acetate, 82% ethylene; 0.7 MI .sup.(5)
EVA #9: 18% vinyl acetate, 82% ethylene; 150 MI
EXAMPLES 22 AND 23
These examples were prepared in a Banbury mixer using the
conditions described in Examples 3 and 4. The composition used
was
16.2% EVA #1
4.0% EVA #2
7.3% Plasticizer
72.5% #9 "Whiting"
The plasticizer used was a mixture of "Santicizer" 334F and
"Circosol" 4240. The relative proportions are indicated in Table
IX, together with the physical properties of the compounds.
Examples C1 and 3 have been included for comparison. Examples 22
and 23 represent most preferred compositions when using a mixture
of the hydrocarbon processing oil and polyester plasticizers. The
data deomonstrate the significant improvement in elongation and
flex crack resistance, while maintaining a comparable level of
tensile strength, when a relatively small amount of the polyester
is used in conjunction with the processing oil.
TABLE VIII ______________________________________ COMPOUNDS BASED
ON E/VA AND E/MA COPOLYMERS Comonomer Type VAc.sup.(1) MA.sup.(2)
Example # 20 21 ______________________________________ Density g/cc
1.82 1.81 Flexural Modulus MPa 31.0 26.2 kpsi 4.5 3.8 Tensile
Strength MPa 1.7 1.4 psi 242 208 Tensile Elongation % 297 301
Tensile Impact J/m.sup.2 109,000 120,700 ft-lb/in..sup.2 51.9 57.5
Crease Test P P ______________________________________ .sup.(1) EVA
#6 .sup.(2) EMA #1: 18% methyl acrylate (MA), 82% ethylene; 2.5
MI
TABLE IX
__________________________________________________________________________
MIXED PLASTICIZERS Plasticizer Component 90% "Circosol" 4240 75%
"Circosol" 4240 100% "Santicizer" (overall conc: 7.3%) 100%
"Circosol" 4240 10% "Santicizer" 334F 25% "Santicizer" 334F 334F
__________________________________________________________________________
Example No. C1 22 23 3 Density g/cc 1.78 1.78 1.79 1.78 Flexural
Modulus MPa 125.5 103 76 18.8 kpsi 18.2 15.0 11.0 2.7 Tensile
Strength MPa 2.8 2.5 2.6 1.9 psi 400 358 379 280 Tensile Elongation
% 23 487 582 365 Tensile Impact J/m.sup.2 40,100 -- -- 121,300
ft-lb/in..sup.2 19.1 57.8 Crease Test P.sup.- P P P
__________________________________________________________________________
EXAMPLES 24 TO 27
These examples were prepared in a Banbury mixer using the
conditions described in Examples 3 and 4. The compositions are
indicated in Table X together with the physical property data. The
results show the effectiveness of the polyethers as a plasticizer
in these highly filled blends (about 72.5% #9 "Whiting"). The
compatibility of this polyether triol is less than that of the
polyester, even though the molecular weights of the two types of
plasticizers are similar. The balance of properties achieved using
the polyether differs from that obtained with the polyester in that
the polyether plasticized compositions are stiffer and somewhat
stronger in terms of tensile strength; flex crack resistance
appears to be unaffected.
The data also show the significantly better performance obtained
with the copolymer triol, Example 25, versus that of the propylene
oxide homopolymer triol, Example 27, in terms of flexural modulus,
tensile elongation, impact strength, and flex crack resistance.
TABLE X
__________________________________________________________________________
POLYETHER PLASTICIZERS
__________________________________________________________________________
Example # 7 24 25 16 26 27 Polymer Type EVA #6 EVA #6 EVA #6 EVA #1
EVA #1 EVA #6 Polymer Conc. wt % 23.3 20.2 23.8 20.2 23.8 23.8
Plasticizer Type Polyester Polyether.sup.(2) Polyether.sup.(2)
Polyester Polyether.sup.(2) Polyether.sup.(3) Plasticizer Conc. wt
% 4.2 7.3 3.7 7.3 3.7 3.7 Density .uparw. g/cc 1.82 .uparw. 1.76
1.79 1.80 1.78 Flexural Modulus .uparw. MPa 90.3 .uparw. 222 26.2
116 288 Kpsi 13.1 DID 32.2 3.8 16.8 41.8 Tensile Strength MPa 2.6
3.4 2.2 3.4 6.2 psi 372 NOT 487 313 499 903 Tensile Elongation %
354 TEST.sup.(1) 213 438 468 23 Tensile Impact .dwnarw. J/m.sup.2
198,000 .dwnarw. 88,600 162,000 209,200 33,900 ft-lb/in..sup.2 89
.dwnarw. 42 77.2 100 16.2 Crease Test P .dwnarw. P P P F
__________________________________________________________________________
.sup.(1) Heavy migration of plasticizer to sample surface during
compression molding. .sup.(2) "Polyglycol" 15200. Molecular weight:
2500; a triol based on a random copolymer of ethylene and propylene
oxides; available from Dow Chemical Co. .sup.(3) "Pluracol" TP
1540. Molecular weight: 1500; a triol based on propylene oxide;
available from BASF Wyandotte.
EXAMPLES 28 AND 29 AND COMPARATIVE EXAMPLES 9 AND 10
These compositions were prepared according to the procedure
described in Examples 3 and 4. All compositions contained 72.5% #9
"Whiting" and 7.3% plasticizer and 20.2% ionomer. These examples
demonstrate that by using, in an ionomer based composition, a
polyester plasticizer instead of a hydrocarbon oil, flexural
modulus and in some cases tensile strength, can be increased
dramatically without affecting elongation significantly. These
properties can be important in sound deadening structures that are
unsupported. The data are summarized in Table XI.
TABLE XI ______________________________________ Example # 28 C9 29
C10 ______________________________________ Ionomer Type (1) (1) (2)
(2) Plasticizer Type "Plasto- "Circo- "Plasto- "Circo- lein" sol"
lein" sol" 9776.sup.(3) 4240 9776 4240 Density, g/cc 1.80 1.70 1.81
1.77 Flexural Modulus MPa 1000 483 1214 593 kpsi 145 70 176 86
Tensile Strength, MPa 12.5 6.5 10.7 11 psi 1816 946 1556 1600
Tensile Elongation, % 11 11 6 11
______________________________________ (1) 8.7% methacrylic acid,
91.3% ethylene, neutralized with Zn.sup.++, 5 MI (2) 10%
methacrylic acid, 90% ethylene, neutralized with Na.sup.+, 1.4 MI
(3) "Plastolein" 9776: polyester plasticizer, Emery Industries,
Inc., mediumhigh molecular weight; specific gravity, 1.08; acid
number, 1.4 mgKOH/g; viscosity @ 100.degree. F., 28 poise;
solidification point -20.degree. C.
EXAMPLES 30 AND 31
These compositions were prepared in a Banbury mixer as described in
Examples 3 and 4. They contain 72.5% #9 "Whiting" filler, 7.3%
polyester plasticizer and 20.2% polymer. The data obtained are
summarized in Table XII. Data for Example 15, containing only the
ethylene/vinyl acetate copolymer used in Examples 30 and 31 are
included for comparison. The incorporation of an EPDM rubber,
especially in small amounts, results in a significant decrease in
flexural modulus without deterioration of other properties.
TABLE XII ______________________________________ Example # 15 30 31
______________________________________ Polymer component(s) EVA #6,
% 20.2 18.2 10.1 EPDM.sup.(1), % 0 2 10.1 Density, g/cc 1.78 1.82
1.82 Flexural Modulus MPa 32.4 19.3 15.2 kpsi 4.7 2.8 2.2 Tensile
Strength, MPa 1.7 1.7 0.9 psi 246 248 136 Tensile Elongation, % 255
338 228 Crease Test P P P ______________________________________
.sup.(1) 68% ethylene/26% propylene/6% 1,4hexadiene; Mooney
viscosity 34 150.degree. C.
EXAMPLES 32-35 AND COMPARATIVE EXAMPLE 11
These compositions were prepared in a Banbury mixer according to
the procedure described in Examples 3 and 4. They all contain 50%
#9 "Whiting" and 2% polyester plasticizer and 48% polymer. The
compositions and the physical property data are summarized in Table
XIII. The data show that both flexural modulus and tensile strength
are increased significantly when the high density ethylene
homopolymer (HDPE) is included in the composition. In terms of
properties required in many sound deadening applications the
optimum benefit with respect to modulus and strength is achieved at
an HDPE concentration of 24 to 38.4% by weight. The peel strength
values shown in Table XIII suggest that the minimum level of the
ethylene copolymer should be about 9.6% by weight in order to
obtain adequate adhesion strength with these compositions.
TABLE XIII ______________________________________ Example # 32 33
34 35 C11 ______________________________________ Polymer
component(s) EVA #6, % 48 38.4 24 9.6 0 HDPE, % 0 9.6 24 33.4 48
Density 1.44 1.45 1.46 1.45 1.47 Flexural Modulus MPa 126 355 806
1771 2181 kpsi 19.7 39.9 126 277 341 Tensile Strength MPa 5.7 4.7
8.9 15 15.3 psi 896 742 1386 2340 2392 Tensile Elonga- tion, % 520
205 16 5 5 Peel strength.sup.(2) gram/inch -- -- 160 140 0
______________________________________ .sup.(1) High density
ethylene homopolymer, density, 0.955 g/cc, 2.8 MI. .sup.(2) Film
samples, 0.004 to 0.006 inches in thickness, were prepared by
compression molding at 175.degree. C. Film strips, 1" in width,
were heat sealed together at a temperature of 130.degree. C., and
at a pressur of 40 psi and a dwell time of 6 sec using a model 12
ASL Sentinel Heat Sealer, produced by Packaging Industries,
Hyannis, Massachusetts. After cooling to room temperature (ca.
25.degree. C.) the samples were peel tested immediately at 12
inch/minute on a peel tester produced by Alfred Suter Co., New
York, New York.
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